aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia

Correspondence e-mail: seikweng/at/um.edu.my

Received July 22, 2008; Accepted July 28, 2008.

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Abstract

The Sn atom in the title compound, [Sn(C4H9)2(C7H5O3)2], is chelated by the carboxyl­ate groups of 2-hydroxy­benzoate liagnds, and exists in a six-coordinate skew-trapezoidal bipyramidal coordination geometry [C—Sn—C = 140.1 (3)°].

We thank the University of Malaya for funding this study (SF022/2007 A, FS339/2008 A) and also for the purchase of the diffractometer.

supplementary crystallographic
information

Comment

Diorganotin dicarboxylates generally exist as monomeric molecules in which the
carboxylate groups chelate in an anisobidentate manner (Tiekink, 1991;
1994).
The R2Sn unit is bent, and the geometry at tin is described as being
skew-trapezoidal bipyramidal (Ng et al., 1987). The title
compound has
been reported in a monoclinic form (Narula et al., 1992).
This structure has one n-butyl group in a W conformation and
the other in a U conformation.
In the present triclinic modification (Scheme I, Fig. 1), both groups adopt a
W conformation.
Intramolecular O-H···O hydrogen bonds are noted (Table 1).

Carbon-bound H-atoms were placed in positions (C–H 0.95 to 0.99 Å) and were
included in the refinement in the riding model approximation, with U(H)
set to 1.2–1.5Ueq(C). The hydroxy H-atoms were similarly constrained
(O–H 0.84 Å) but the hybridization of the oxygen atoms was assumed to be
sp2.

The final difference Fourier map had a peak of 2.57 e Å-3 at 1.5 Å
from the O5 and O6 atoms, and a deep hole of -1.40 e Å-3 at 1.5 Å
from the H12 atom.